jquery心形讚著重效果的簡單實現

<div class="stage">
 <div class="heart"></div>
</div>

.heart {
 width: 100px;
 height: 100px;
 background: url("") no-repeat;
 background-position: 0 0;
 cursor: pointer;
 -webkit-transition: background-position 1s steps(28);
 transition: background-position 1s steps(28);
 -webkit-transition-duration: 0s;
     transition-duration: 0s;
}
.heart.is-active {
 -webkit-transition-duration: 1s;
     transition-duration: 1s;
 background-position: -2800px 0;
}
  
body {
 background: -webkit-linear-gradient(315deg, #121721 0%, #000000 100%) fixed;
 background: linear-gradient(135deg, #121721 0%, #000000 100%) fixed;
 color: #FFF;
 font: 300 16px/1.5 "Open Sans", sans-serif;
}
  
.stage {
 position: fixed;
 top: 50%;
 left: 50%;
 -webkit-transform: translate(-50%, -50%);
     transform: translate(-50%, -50%);
}